Within the power generation industry, large-scale power generators convert mechanical energy, typically the energy output of a turbine rotor, into electrical energy. Such power generators typically include a frame-supported stator and a rotor positioned to rotate within the stator, so as to induce electrical current through conductors moving through a magnetic field set up within the stator. The current may be conducted to a power plant bus for eventual power distribution to consumers, commercial establishments, and any other users of electrical power.
Components within a typical generator frame require cooling to prevent overheating thereof. A cooling medium that is often used in such generator frames is pressurized hydrogen gas, which may be introduced into the generator frame from an external source. While it is preferable to minimize leakage of the hydrogen gas out of the generator frame, a small amount of hydrogen gas may leak through shaft seal assemblies, gasketed covers and sealed joints, which are typically used to prevent the hydrogen gas from escaping from the generator frame. Typically, the pressure of the hydrogen gas within the generator frame is controlled by a self-operated pressure regulator set at a desired operating pressure within the generator frame. The desired operating pressure is set between upper and lower alarm pressures to maintain the pressure within the generator frame at a safe and acceptable level.
To indicate undesired high levels of leakage of the hydrogen gas out of the generator frame, a flow meter is typically used to monitor input of the hydrogen gas entering the generator frame. Disadvantages of such flow meters include cost and complexity of the system. Alternatively, hydrogen gas consumption can be measured manually by measuring a drop in gas pressure over a time interval. The manual process requires manual operation of the hydrogen supply and may not provide a timely indication of a sudden change in hydrogen gas consumption.